Do aliens really exist

     I remember when I was in primary school, my friend borrowed a book on alien life in the library. She was so absorbed in the book that she refused to leave her book on her way home and was walking along. I said to her, "is this book so good?"" "It's 3," he said. "There's a story about some people communicating with aliens.". As she looked at it, she replied, "I shook my head helplessly. Then she said in a solemn manner," if we met aliens on the way, we wouldn't be afraid. We could communicate with them. "My face said in surprise:" don't say Chinese aliens?" "No, the story recorded in this book says that aliens are telepathic. Suddenly I know to admire her.
     The aliens really exist? We often hear when UFOs, alien stories, are those described are scared of odd shape aliens, like monster like hard skin, big head, red eyes. When we grow up, we are no longer interested in such stories as aliens. But I'm sure many people still have a little interest in aliens!
     First of all, our earth is full of vitality, not only with highly intelligent creatures like human beings, there are all kinds of animals and plants, but also because of the existence of life, make our earth more beautiful, let the earth in the universe special. For, as yet, man has not found other living things on his planet. We can't find any living beings on our neighbor planet, but the universe is far away. Maybe aliens are in a corner of the universe. After all, we are in the Milky Way of solar system, the solar system and the Milky Way, whether there is any body? Perhaps when more advanced science and technology, scientists will be able to solve this question.
     As we all know, life is indispensable to water, so scientists are trying to find whether there is water on other planets, because there is water, there is the existence of life. The scientists found no liquid water on other planets like earth, they found over sea ice as ice in the moons of Jupiter, that ice may have liquid water, but scientists have yet to study. In Daniel Wu's film "Europa report", the six astronauts on a secret mission to Europa, was an unidentified attack in the middle of a mission, it is with hair standing on end.
     But do aliens really need water? Maybe on the planet without water or oxygen, aliens have become accustomed to the environment of their planet, and unlike living things on earth, they need water and oxygen to survive. Perhaps in our eyes, poisonous substances are essential for them to come.
     In the end, aliens do not exist? If so, what form do they exist? Is it a single cell, an animal, a plant, or a higher organism like humans? If they are more civilized than we are, will they invade the earth or try to communicate with the earth? These problems are likely to be solved in the future.